Method for measuring the rate of penetration of an equipment progressing in a well

摘要: The method comprises using a transmitting unit and at least two receiving units (8,10) arranged in different places along well equipment (2). Each forms an image or signature of wall portions which pass it. signatures formed by the lower (8) when is being lowered into are stored upper (10) stores coming from were previously unit. A comparison (for example correlation) respectively allows common portion has produced substantially identical compared to be identified. time interval between formation measured rate penetration calculated. As application invention for measurement true tool measuring sonde.